Tuesday, September 21, 2010

Piedmont Savanna Ecology Course

Some spaces are still available for Piedmont Savanna Ecology, a new course offered by the UNC Botanical Gardens.

Course title: Piedmont Savanna Ecology
Course location: UNC Botanical Garden

Date/Time: Saturdays, Oct 2, 9, 16, 23; 1:00–4:30 pm
Instructor: Nicolette Cagle, Ph.D.

Course description: In this course, students explore the rare Piedmont savanna plant community: its ecological history and the relative roles of climate, disturbance, and humans in grassland establishment and persistence. Students learn about the soil, flora, and fauna of the Piedmont savanna, emphasizing rare and threatened species, and examine current and future status of this rare Piedmont plant community. We end with a field trip to two restoration sites. No pre-requisites. Fee: $125 ($110 NCBG members)

If you have any questions or need a registration form, please feel free to contact me at nicolette.cagle (at) gmail.com.

Echinacea laevigata at Penny's Bend, Durham, NC (July 2008; Photo by N. Cagle)

Monday, September 6, 2010

Laurel Bluffs Trail along the Eno River (Durham, NC)

Overview: Located in north Durham, the Laurel Bluffs Trail offers a 5 mile out-and-back hike. The trail winds through Piedmont forest along the Eno River, starting at Eno River State Park's Pump Station trail and ending at Guess Road. The trail tightly hugs the river, deviating over ridge tops for only a couple short stretches. Highlights include large (2 - 2.5 ft in diameter) tulip trees and beeches, as well as the ruins of an old hunting lodge and the Guess Mill dam. Hiking on a Sunday morning, we encountered only one runner and one bustling hiker from a nearby neighborhood.

From Laurel Bluffs trail

Directions: The trail can be accessed from Eno River State Park's Pump Station trail (see map). To arrive at the Pump Station trail, take Guess Road north about 0.9 miles from exit 147 off I-85. Turn left at Carver Street, and continue 1.7 miles. Turn right at Rose of Sharon, go 0.6 miles and turn left at Valley Springs Road. Continue on Valley Springs for 0.4 miles, turning left at Rivermont, the first gravel road on the left. Pump Station trail will be half a mile down on the righthand side of the road, immediately before the bridge.

The trail can also be reached by descending a steep set of steps on the west side of Guess Road at the bridge that crosses the Eno River (see satellite image).

Observations & Ponderings: The Laurel Bluffs trail provides a quiet walk back through time, when the Eno River had a bustling mill economy. In the late 18th and early 19th centuries, mills along the Eno River ground grain into flour and turned raw timber into usable lumber. According to Duncan Heron (see article here), below Hillsborough, NC there were about 15 mills along Eno River, strategically located in stretches where hard igneous and metamorphic rock jutted out into the river, making it easier to construct a dam and mill.

Jean Anderson (see article here), writing about old Orange County mills, states that mills were "viewed as good investments" and cost between $1,000 and $6,500 to start up. Mills usually took about 10% of the market value of the grain they ground, and Piedmont mills were known to make an annual profit of around $1,000 - $2,000. Despite their profitability, Eno River mills were extremely vulnerable to heavy rains and their associated flooding. According to local lore, Synott's Mill, the first built along the Eno River in 1752, fell victim to a devastating flood.

Anderson goes on to write that mills were once central to 19th century Piedmont society. Local mills provided a place for men to swap stories, politicians to garner support and postal riders brought news from outside the rural Piedmont. Although these mills are no longer crucial to the Piedmont community, they do provide a charming backdrop for considering our rich history, while allowing us to revel in the beauty of our boulder-strewn, forest-fringed Eno River.

Below are photos of the Laurel Bluffs trail (photos by Nicolette Cagle, taken on 5 September 2010):

From Laurel Bluffs trail

Upland stretch of the Laurel Bluffs trail (Photo by N. Cagle, Sep 2010)

From Laurel Bluffs trail

Fish Dam Island along the Laurel Bluffs trail (Photo by N. Cagle, Sep 2010)

From Laurel Bluffs trail

Remnants of the old hunting lodge along the Laurel Bluffs trail (Photo by N. Cagle, Sep 2010)

From Laurel Bluffs trail

Remanants of Guess Mill Dam along Laurel Bluffs trail (Photo by N. Cagle, Sep 2010)

From Laurel Bluffs trail

Old mill stone along Laurel Bluffs trail (Photo by N. Cagle, Sep 2010)

From Laurel Bluffs trail

Spill way of the mill along Laurel Bluffs trail (Photo by N. Cagle, Sep 2010)

Sunday, September 5, 2010

GREAT EXPECTATIONS: September in the Piedmont

Birds.− September brings a number of winter residents back to the Piedmont, including the yellow-bellied sapsuckers, an occasional red-breasted nuthatch and a number of wrens (winter, sedge, marsh) and sparrows (swamp and white-throated). Migrant warblers continue to pass through North Carolina as they head towards the neotropics for the winter. Birders may even see snowy egrets, little blue herons and tricolored herons, which won’t return again to the Piedmont until early April.

Butterflies.− Expect to see a pulse of cloudless sulphurs, little yellows and sleepy oranges this month. Swallowtail sightings will likely drop-off by mid-month, with the exception of the black swallowtail. Butterfly watchers can also expect to see gray and red-banded hairstreaks, gulf and variegated fritillaries, as well as an increased number of viceroy sightings. Monarchs may be seen as they migrate southward to their winter residence in Mexico.

The Carolinas are home to five families of butterflies: the skippers (Hesperiidae), gossamer wings (Lycaenidae), brush-foots (Nymphalidae), swallowtails (Papilionidae) and the sulphurs and whites (Pieridae). Each of these families can be divided into a number of sub-families, each having distinct identifying characteristics. This month, we will consider the sulphurs (subfamily: Coliadinae), some species of which are on the rise this month. Members of the Coliadinae are normally some shade of yellow, often having dark markings on their wings. Males and females usually differ in appearance (i.e., they are sexually dimorphic), and their coloration may vary with the seasons. For example, the sleepy orange if often bright yellow in the summer, but their hindwings often become rust-colored in the fall. Male sulphurs can often be found congregating around mud-puddles, where they obtain water and salts. Sulphurs are found in open, disturbed habitat and they over-winter as larvae.

Reptiles & Amphibians.− Continue to keep an eye out for snakes and turtles, especially baby box turtles. Skinks are also out in abundance. Although you may still hear frogs and toads calling this month, large choruses won’t start up again until January.

Other Insects.− This month, expect an increase in praying mantis and spider activity. Female garden spiders (Argiope aurantia) will be guarding egg cases this time of year. In fact, garden spiders breed only once a year. Males garden spiders will court the females by plucking strands on her web, and die after mating, sometimes being consumed by the female. The female garden spider will then lay her eggs (usually at night), covering them in layers of silk. One to four egg sacs, with thousands of eggs inside, are usually suspended in the middle of her web, where she guards them against predation until she dies with the first hard frost. In spring, young garden spiders will emerge from the brown-silk sac. Some offspring may remain closeby, but others exude a strand of silk that gets caught in the wind, carrying them to a new home.

In Bloom this Month.− Be on the lookout for some striking September flowers:

In Bloom:
WINGSTEM – Actinomeris alternifolia
WHITE SNAKEROOT – Ageratina altissima
PARTRIDGE PEA – Chamaechrista fasciculata
TURTLEHEAD – Chelone glabra
BEECHDROPS – Epifagus virginiana
DEVIL'S-GRANDMOTHER - Elephantopus tomentosus
BONESET – Eupatorium perfoliatum
BLACK-EYED SUSAN – Rudbeckia sp.
TRAILING WILD BEAN - Strophostyles helvula
GREAT LOBELIA – Lobelia siphilitica
DOWNY LOBELIA – Lobelia puberula
SMALL SKULLCAP – Scutellaria parvula
AXILLARY GOLDENROD – Solidago caesia
GOLDENROD(S) – Solidago spp.

In Fruit:
HEARTS-A-BUSTIN’ – Euonymus americanus
MUSCADINES – Vitis rotundifolia

Historical Anecdote: Sweet gum – Liquidambar styraciflua
“This sweet gum is a noble tree, that might well impress anyone new to the sight of it. And the sight is a common one, for it grows along any fence row, in piedmont Virginia, beside any country road of the Carolinas, in any field abandoned by agriculture and growing up to scrub pine and dogwood. It comes up in company, in these upland sites, with sassafras and red cedar, and may be known by its beautiful star-shaped leaves. Their upper surface has a star-like glister, but unlike most shining leaves, those of the sweet gum are not dark at maturity but a light, gay yellow-green. Crushed in the fingers, they give out a cleanly fragrance; on the tongue they have a tart taste. Foliage so odd and yet so attractive would make any tree conspicuous.” – Donald Culross Peattie, 1948, A Natural History of Trees of Eastern and Central North America

National Audobon Society. 1980. Field Guide to North American Insects and Spiders. New York, New York: Chanticleer Press.

Cook, Dave. 2001. The Piedmont Almanac. Chapel Hill, North Carolina: Mystic Crow Publishing.

Daniels, J. C. 2003. Butterflies of the Carolinas. Cambridge, MN: Adventure Publications, Inc.

LeGrand, H. E. Jr. 2009. Notes on the Butterflies of North Carolina. Available at: